Scaffold staging



1964 F. s CALLAHAN 3,145,801

SCAFFOLD STAGING Filed April 25, 1963 INVENTOR.

FREDERICK S. CALLAHAN M x-MW ATTORNEYS United States Patent *ce 3,145,801 SCAFFOLD STAGING Frederick S. Callahan, 18 Cleaves St., Auburn, Maine Filed Apr. 23, 1963, Ser. No. 274,990 2 Claims. (Cl. 182-63) This invention relates to a scaffold staging designed for use on bridges supported by piers or on other equivalent structures where access to the underside is desired. Most modern highway bridges of any considerable size are of structural steel on which a road surface of concrete, asphalt or the like is laid. For proper maintenance the steelwork should be painted at intervals, this requiring a suitable support for the painters under the bridge. If the bridge is supported on piers and has no superstructure, a staging can be slung under the bridge and shifted along as neeed until it comes to a pier. Heretofore it has been necessary to dismantle the staging sufficiently to get it past the pier and to reassemble it on the other side of the pier to be shifted along until the next pier is reached.

According to the present invention, the staging includes a horizontal platform supported under the bridge by offset framework at one side of the bridge connecting the platform to a carriage which rides upon the bridge, and can be advanced as desired when the position of the platform is to be shifted. The framework is so constructed as to permit the platform to be swung down far enough to pass a pier so that the entire structure can be moved past the pier, whereupon the platform is readily swung back to its horizontal position for use.

For a more complete understanding of the invention, reference may be had to the following description thereof, and to the drawings, of which FIGURE 1 is an end elevational view of a staging embodying the invention, in position for use; and

FIGURE 2 is a side elevation of the staging shown in FIGURE 1.

A traveling staging embodying the invention is shown as mounted on a bridge having a roadway supported on beams 12 which extend from pier to pier, part of one such pier 14 being shown in FIGURE 1. The staging comprises a carriage consisting of one or more platforms 20 mounted on framework including parallel beams 22 which extend across and are secured to transverse beams 24. Under the beams 24 are suitable wheels 26 which travel on the roadway 10 so that the staging can be advanced as required, any suitable motive means (not shown) being employed as desired. The frame of the carriage is stiffened by diagonal braces 28, 30, and wheels 32 are supported by brackets 34 to bear against the side of a raised border or parapet 36 on the roadway 10 to keep the staging from rolling off the edge of the bridge.

For a wide bridge, the carriage beams 22 are preferably arranged to extend across only half of the width of the roadway, but these beams project out beyond the side of the bridge as shown. The framework also includes vertical beams 40 secured to the beams 22 beyond the side of the bridge, and extending down therefrom. Pivotally attached as at 42 to the lower ends of the vertical Patented Aug. 25, 1964 beams 40 are normally horizontal beams 44 which extend under the roadway 10 preferably to the mid point thereof and support a platform 46 directly beneath the carriage and at a convenient distance below the roadway for painters to have access to the steelwork 12.

To maintain the platform 46 in its horizontal position, the beams 44 extend out beyond the pivots 42, the outer ends being pivotally attached as at 48 to struts 50 which extend upward to or past the respective beams 22 and are secured thereto by locking elements such as pins 52 which are removable to release the platform to swing to a tilted position. Diagonal cross-braces 54 help to keep the vertical beams 40 parallel to each other.

To counterbalance the platform 46 which is rockable about a horizontal axis through the pivots 42, a weight is mounted on the portions of the floor beams 44 which extend outward beyond the pivots 42.

When the staging is in use, the platform 46 is horizontal and the whole structure is moved along the roadway as required until the platform comes to a pier 14. Then the pins 52 are removed and the platform 46 is swung down far enough to clear the pier. Since the counterweight 60 balances the platform, this is easily done. The staging is then moved along until the platform is on the other side of the pier, whereupon the platform is restored to its horizontal position and locked in such position by insertion of the pins 52 in their holes.

To keep the staging from being capsized by the counterweight 60, the top platform 20 is made heavy enough to hold the carriage down on the roadway.

I claim:

1. A staging comprising a carriage having supporting wheels and adapted to travel along the roadway of a piersupported bridge, said carriage having framework adapted to extend out beyond the edge of the bridge, beams secured to and projecting down from said framework, a platform pivoted to said beams on a horizontal axis below the level of the bridge and normally located underneath said carriage, said platform having members extending beyond the pivot, means normally maintaining said platform in a horizontal position, said means including struts pivotally attached at their lower ends to said extending portions of the platform members and releasably attached to said framework.

2. A staging as described in claim 1, and means on said extending platform members counterbalancing the platform.

References Cited in the file of this patent UNITED STATES PATENTS 1,630,626 Menneiley May 31, 1927 2,639,950 Wheeler May 26, 1953 2,669,490 Kaufman Feb. 16, 1954 3,035,659 Sims May 22, 1962 3,076,522 Goodell Feb. 5, 1963 FOREIGN PATENTS 221,337 Australia Apr. 6, 1959 

1. A STAGING COMPRISING A CARRIAGE HAVING SUPPORTING WHEELS AND ADAPTED TO TRAVEL ALONG THE ROADWAY OF A PIERSUPPORTED BRIDGE, SAID CARRIAGE HAVING FRAMEWORK ADAPTED TO EXTEND OUT BEYOND THE EDGE OF THE BRIDGE, BEAMS SECURED TO AND PROJECTING DOWN FROM SAID FRAMEWORK, A PLATFORM PIVOTED TO SAID BEAMS ON A HORIZONTAL AXIS BELOW THE LEVEL OF THE BRIDGE AND NORMALLY LOCATED UNDERNEATH SAID CARRIAGE, SAID PLATFORM HAVING MEMBERS EXTENDING BEYOND THE PIVOT, MEANS NORMALLY MAINTAINING SAID PLATFORM IN A HORIZONTAL POSITION, SAID MEANS INCLUDING STRUTS PIVOTALLY ATTACHED AT THEIR LOWER ENDS TO SAID EXTENDING PORTIONS OF THE PLATFORM MEMBERS AND RELEASABLY ATTACHED TO SAID FRAMEWORK. 